Adjustable weight golf clubs

ABSTRACT

The present invention relates to golf clubs having a movable weight which may be used to adjust the center of gravity of the golf club head. The golf club may include a slidable weight movable to various positions along a slot between the heel and the toe of the club. The head may include a cavity shaped to receive an insert. In one embodiment, a slidable weight consisting of a screw and a weight which may engage with each other may be configured to move along the length of the insert. During assembly, the weight may be inserted into an opening in the end of the insert and slid along a close fitting channel running the length of the insert. The weight&#39;s position along the channel may be secured by engaging the screw and tightening down the screw with a portion of the insert secured between the screw head and the weight. The assembled insert and slidable weight may then be press fit into the cavity in the head. By adjusting the position of the weight and screw within the insert, the center of gravity of the golf club may be adjusted.

FIELD OF THE INVENTION

The present invention relates to golf clubs. More specifically, the present invention relates to golf clubs having a movable weight which may be used to adjust the center of gravity of the golf club head.

BACKGROUND OF THE INVENTION

When golf clubs are designed and manufactured, they are typically given specific weight characteristics to achieve performance standards that the manufacturer deems desirable for a large number of golfers. Specifically, manufacturers may wish to adjust the overall weight of the shaft of the club, the overall weight of the head of the club, the weight distribution along the shaft of the club and/or the weight distribution within the head of the club. Each change in weight has different results for different golfers depending on a golfers' height, weight, ability and swing type.

Often, manufactures distribute the weight of the head of the club by casting more mass into the toe of the club, the heel of the club or both the toe and the heel. This creates a “sweet spot,” the ideal location to strike a golf ball, located in or near the center of the club because of the weight distribution. However, because of the inherent differences between each golfers' size, swing and ability, this location for the sweet spot is not always ideal.

Ideally, a manufacturer would create a set of golf clubs with the weight distributed such that the sweet spot is located at each individual golfer's ideal location to strike the ball. However, “custom” golf clubs are often not economically feasible for most golfers due to the cost associated with tailoring clubs to individual golfers. Additionally, manufacturers are not able to pre-manufacture a large number of clubs for sale as the manufacturing process must account for any changes required by each individual golfer. Therefore, manufacturers often produce adjustable weight golf clubs in order to provide each golfer with clubs which may be at least partially tailored to their individual swing characteristics.

One previous attempt at providing such an adjustable weight golf club includes the insertion of different value weights into or on to the club head. These weights are generally either perimeter weight inserts, weighted plugs or weighted plates. They may be inserted into different locations inside, or attached around the outside, of the club head. For a golfer to adjust the weight of these clubs, the weights must be removed and replaced with separate weights each time a change is desired.

Another previous attempt at providing an adjustable weight golf club has been to provide weighted screws located at specific locations inside and/or around the outside of the club head. A golfer may tighten or loosen the screws in order to alter the distribution of weight along the threaded channel which receives the screw in the head of the club.

One drawback of previous adjustable weight clubs is that weight adjustment may be time-consuming because the weights may need to be detached and reattached or adjusted using special tools. Further, adjustment of the weight may include the removal of a cover plate or similar device merely to obtain access to the weights. As such, when a golfer wishes to make a quick change or an alteration to the weight of the club (as may be desirable during play), the golfer is unable to do so without engaging in the laborious process of switching or adjusting the weights.

Another drawback of these clubs is that the potential adjustability is limited. A golfer may only adjust weights in certain specific locations and the location of the weights is limited to those locations chosen by the manufacturer. Therefore, each golfer's options for the distribution of weight in the club head is limited to the adjustment of screws or weights placed at specific locations around the club head. These locations may not provide for the ideal weight adjustments for each golfer.

Finally, the previous adjustable weight golf clubs involve many metal parts which must be manufactured separately and fit together. As a result, the manufacture and assembly of the clubs is costly and time-consuming. Where metal parts must be fit together, there are specific tolerances which must be met in order to ensure that each part will fit with the other parts and that the club as a whole will function properly. Further, the assembly of these clubs is difficult because of the number of parts which must be fit together.

As such, there is a need for an easily manufactured adjustable weight golf club which provides golfers with the ability to easily adjust the center of gravity of the golf club at many different locations.

SUMMARY OF THE INVENTION

The present invention relates to golf clubs. More specifically, the present invention relates to golf clubs having a movable weight which may be used to adjust the center of gravity of the golf club head.

The present invention may include an adjustable weight golf club. The golf club may comprise a shaft, a head a movable weight and an insert for slidably receiving the movable weight. In one embodiment, the insert may be positionable within the head of the golf club.

The present invention may also include a method of manufacturing an adjustable weight golf club. The method may include the steps of manufacturing a golf club head configured to attach to a golf club shaft and manufacturing an insert configured to slidably receive a movable weight. Additionally, the method may include the step of positioning the insert within the golf club head.

These and other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing out and distinctly claiming the present invention, it is believed the same will be better understood from the following description taken in conjunction with the accompanying drawings, which illustrate, in a non-limiting fashion, the best mode presently contemplated for carrying out the present invention, and in which like reference numerals designate like parts throughout the Figures, wherein:

FIG. 1A shows an exploded view of an adjustable weight golf club according to one embodiment of the present invention.

FIG. 1B shows an adjustable weight insert for use with one embodiment of the adjustable weight golf club of the present invention.

FIGS. 2A, 2B and 2C show several locations of a slidable weight in a golf club head according to one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure will now be described more fully with reference to the Figures in which various embodiments of the present invention are shown. The subject matter of this disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein.

FIG. 1A shows an exploded view of an adjustable weight golf club head 100 according to one embodiment of the present invention. The head 100 includes a main body having a heel 30, a toe 40, a top 90, a sole 50, a first cavity 70, a second cavity 60 and a hosel 20. The hosel 20 may be connected to any suitable golf club shaft 10 known in the art including, but not limited to, metal and carbon fiber shafts. Additionally, the head 100 includes a ball striking surface 80 which may include grooves (not shown) etched or machined into the side of the surface 80 which makes contact with a golf ball (not shown).

In one embodiment, the body and the ball striking surface 80 of the head 100 according to the present invention are manufactured entirely from metal. However, alternative materials such as carbon fiber or any other suitable material with sufficient strength to withstand the striking of a golf ball may be used. For example, in one embodiment of the present invention, the main body and the striking surface 80 are both manufactured from stainless steel. In other embodiments, however, it is well known to manufacture the body or the striking surface out of other metals, such as titanium, aluminum, zinc, liquid metal, carbon steel, different grades of stainless steel or other lightweight materials having sufficient strength to withstand the forces associated with striking a golf ball.

The ball striking surface 80 and the main body of the head 100 may be manufactured using any of a number of suitable techniques known in the art of golf club manufacturing. In one embodiment, a Stainless steel cast body and a Stainless steel ball striking surface 80 are separately manufactured. Thereafter, the ball striking surface 80 may be attached to the body using any suitable means for attaching two pieces of metal including, but not limited to, adhesive, epoxy, screws or welding. In an alternative embodiment, the body and the ball striking surface 80 may be machined as one single molded piece, thus eliminating the need to attach two pieces of metal together.

As illustrated in FIG. 1A, and as mentioned briefly above, the body of the head 100 may be manufactured with two openings 60 and 70. The head 100 may or may not include the first cavity 70 depending on the desired overall weight of the body of the club head 100. In embodiments excluding the first cavity 70, the main body in the area illustrated as the first cavity 70 (FIG. 1A) may be either solid or hollow, depending on the desired overall weight of the body of the club head 100.

The second cavity 60 may be formed by computer numerical control (“CNC”) machining, casting or another similar method for manufacturing known in the art. As illustrated in FIG. 1A, the second cavity 60 may be elongated so that it runs substantially parallel to the sole 50 from the heel 30 to the toe 40. The second cavity 60 is shaped to receive an insert 150 which, as discussed in greater detail below, may be used to alter the center of gravity of the golf club head 100. As will be readily apparent to one of skill in the art, the second cavity 60 (and the weighted insert 150) may be manufactured to be located at any points within the club head 100 and may have any shape, depending on how the manufacturer desires to allow the center of gravity to be altered. Further, one or more additional cavities for receiving additional inserts may be placed within the club head 100 to allow for greater flexibility in altering the center of gravity of the club head 100.

FIG. 1B shows an adjustable weight insert 150 for use with one embodiment of the adjustable weight golf club of the present invention. As discussed above, the insert 150 is intended to be inserted into the second cavity 60 of the golf club head 100 to allow a user to adjust the center of gravity of the head 100. The insert 150 may include an injection molded or blow molded plastic body 110 of a suitable shape to be received by the second cavity 60. Alternatively, the body 110 may also be manufactured from metal or other suitable materials known in the art. The body 110 may include a hole 120 at one or both ends which may be configured to receive a slidable weight, as discussed in detail below.

In one embodiment, the slidable weight consists of a screw 130 and a weight 140. The screw 130 and weight 140 may be configured to engage with each other, as illustrated in the figures. The screw 130 may be a conventional screw, which requires a tool for adjustment as required by the United States Golf Association (“USGA”). However, it may also be of the type which may be tightened or loosened by hand, without the use of tools. During assembly, the weight 140 may be inserted into the opening 120 at one end of the body 110 and slid along a close fitting channel running the length of the insert, as illustrated in FIGS. 1A and 1B. The screw 130 may then be fit into a threaded hole in the weight 140 so that the two are threadably engaged with one another. The slidable weight's position along the channel may be secured by engaging the screw 130 with the weight 140, with a portion of the body 110 being secured between the head of the screw 130 and the weight 140.

While the embodiment of the present invention shown in the figures illustrates the use of a screw 130 and weight 140 combination for the slidable weight, it will be readily apparent to one of skill in the art that alternative embodiments may be utilized. For example, holes may be manufactured inside of the body 110 of the insert 150 and the slidable weight may include a pin and spring apparatus which may engage with the holes to hold the weight at a specific position.

Once the insert 150 is assembled, it may be positioned in the second cavity 60 of the golf club head 100, as illustrated in FIG. 1A. The insertion of the insert 150 into the cavity 60 may serve to effectively close hole 120, thus ensuring that the weight 140 remains within the body 110 of the insert 150 during use. In one embodiment, the insert 150 is press fit into the cavity 60. In alternative embodiments, epoxy or adhesive may be used to attach and hold the insert 150 within the second cavity 60. In other embodiments, mechanical notches may be formed on the outside of the body 110 of the insert 150 which may engage with the interior walls of the second cavity 60 to hold the insert 150 within the cavity 60 without the use of additional materials. Additionally, it is contemplated that the insert 150 may be formed from metal, as discussed above, and welded into the second cavity 60. Further, it is contemplated that the insert 150 be removable by the user in the event that the user wishes to interchange different amounts of weight to further customize the weight of the golf club head 100.

In one embodiment, the slidable weight (including both the screw 130 and the weight 140) has a total weight of approximately 25 grams. Of course, it will be readily apparent to one of skill in the art that the combined weight of the slidable weight may be of any weight depending on the amount by which a user wishes to alter the center of gravity of the club head 100, as discussed below. The total desired weight may be dependent on the size of the club, the number of total slidable weights within the club head, the position of the slidable weights on the club head and other factors.

Once the entire club head 100 is assembled, a user may adjust the center of gravity of the head 100 by moving the slidable weight along the length of the insert 150. FIGS. 2A, 2B and 2C show several locations of a slidable weight in a golf club head 100 according to one embodiment of the present invention. In FIG. 2A, the slidable weight (consisting of a screw 130 and weight 140) is located at the center of the body 110 of the insert. Thus, the center of gravity of the club head illustrated in FIG. 2A is at, or close to, the center of the sole. By loosening the screw 130 and moving the slidable weight toward the heel, as illustrated in FIG. 2B, a user may shift the center of gravity of the club head to be closer to the heel. Conversely, by loosening the screw 130 and moving the slidable weight towards the toe, as illustrated in FIG. 2C, a user may shift the center of gravity of the club head to be closer to the toe.

Thus, dependent on a golfer's swing type and where on the ball striking surface the golfer makes contact with the ball during play, the golfer may manipulate the center of gravity of the club head to a position that will perform best for that individual. Therefore, a golfer who tends to hit golf shots off of the toe of the club head can reposition the weight towards the toe for better performance, increased distance and more solid feeling shots. The same is true for a golfer who hits shots towards the heel of the golf club head. As such, multiple golfers may be able to customize and use the same golf club or clubs.

One advantage of the adjustable weight golf club of the present invention is that the golf club head 100 may be easily manufactured and produced by a manufacturer. Because the insert may be formed of molded plastic and press fit into the club head, the tolerances associated with manufacturing are not as strict as those associated with the manufacture of all-metal parts. Additionally, the simple construction of the club allows for a manufacturer to cheaply produce a large number of clubs which may then be at least partially customized by each consumer. This allows for the manufacturer to market a user-customizable golf club at competitive prices.

Further, because the golf club of the present invention allows for the placement of the adjustable weight at multiple locations on the head, each user may easily tailor the club's performance to their swing type. Because the weight may be adjusted with a simple screw or pin, each user may alter the center of gravity with the use of minimal tools (if any) and in a minimal amount of time. Additionally, if the insert were to fail or break, or if a user wishes to alter the amount of movable weight, the present invention allows for easy replacement of the weight and/or insert rather than requiring a user to purchase an entirely new adjustable weight golf club head. Further, different weights (i.e. heavier or lighter) may be used by different users.

While the figures and above description describe an adjustable weight golf iron, it should be realized that the present invention is intended to incorporate any type of golf club, including woods, iron-woods and putters. One of ordinary skill in the art will realize that a cavity may be formed in the head of any type of golf club which may receive an insert having a slidable weight. Additionally, it should be realized that the present invention may be incorporated on any type of golf iron and, ideally, will be incorporated in each iron in a matching set of irons. Thus, this disclosure is not intended to be limited in any way only to golf irons or to any specific type of golf iron.

The foregoing descriptions of specific embodiments of the present invention are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations are possible in view of the above teachings. While the embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to best utilize the invention, various embodiments with various modifications as are suited to the particular use are also possible. The scope of the invention is to be defined only by the claims appended hereto, and by their equivalents. 

1. An adjustable weight golf club comprising: a shaft; a head; a movable weight; and an insert for slidably receiving said movable weight; wherein said insert is positionable within said head.
 2. The golf club of claim 1, wherein said insert is made of non-metal material.
 3. The golf club of claim 1, wherein said insert is made of metal material.
 4. The golf club of claim 1, wherein said insert is held within said head using a press fit.
 5. The golf club of claim 1, wherein said insert includes means for attaching said insert to said head.
 6. The golf club of claim 1, wherein said insert is held within said head using an adhesive or epoxy.
 7. The golf club of claim 1, wherein said insert includes a hole for receiving said movable weight and wherein the hole is closed upon positioning said insert in said head.
 8. The golf club of claim 1, wherein said insert is removably positioned within said head.
 9. The golf club of claim 1, wherein said insert includes an opening providing access for a user to adjust the location of said movable weight when said movable weight is slidably received by said insert.
 10. The golf club of claim 1, wherein said movable weight includes a locking portion, the locking portion having at least a first and a second position.
 11. The golf club of claim 10, wherein when the locking portion is in a first position, said movable weight is prevented from sliding within said insert and when the locking portion is in a second position, said movable weight is permitted to slide within said insert.
 12. The golf club of claim 10, wherein the locking portion is a threaded screw.
 13. The golf club of claim 10, wherein the locking portion is a spring and pin combination configured to engage with holes within said insert.
 14. The golf club of claim 2, wherein said insert is made of blow molded plastic or injection molded plastic.
 15. The golf club of claim 1, wherein said head includes a top, a sole, a heel and a toe and wherein said insert is positionable between said top and said sole and between said heel and said toe.
 16. The golf club of claim 15, wherein said head further includes a ball striking surface having a first and a second side, the first side being configured to strike a golf ball and said insert being positionable on the second side.
 17. A method of manufacturing an adjustable weight golf club, the method comprising: manufacturing a golf club head configured to attach to a golf club shaft; manufacturing an insert configured to slidably receive a movable weight; and positioning the insert within the golf club head.
 18. The method according to claim 17, wherein the step of positioning includes holding the insert within the head using a press fit.
 19. The method according to claim 17, further comprising the step of slidably inserting a movable weight into the insert prior to the step of positioning the insert within the golf club head.
 20. The method according to claim 19, wherein the movable weight is inserted into the insert using a hole in the insert. 